The most popular ARM processor for microcontroller applications is the ARM7TDMI. It's a 32-bit processor that is typically found in the 50-60MIPS range (with hardware multiply), and generally includes plenty of i/o, program and data memory at a very reasonable cost (as low as $1.50 for an NXP LPC2101). A number of companies produce microcontrollers based on ARM7 - ATMEL, Philips/NXP, Analog Devices, etc. A wealth of development tools are available, including free compilers (GNUARM), RTOS, Linux, etc. We use the Philips/NXP LPC2106 as our main processor, and are very pleased with the ease of software development and hardware integration. You'll find a nice overview here - http://en.wikipedia.org/wiki/ARM_architecture

The most popular ARM processor for microcontroller applications is the ARM7TDMI. It's a 32-bit processor that is typically found in the 50-60MIPS range (with hardware multiply), and generally includes plenty of i/o, program and data memory at a very reasonable cost (as low as $1.50 for an NXP LPC2101). A number of companies produce microcontrollers based on ARM7 - ATMEL, Philips/NXP, Analog Devices, etc. A wealth of development tools are available, including free compilers (GNUARM), RTOS, Linux, etc. We use the Philips/NXP LPC2106 as our main processor, and are very pleased with the ease of software development and hardware integration. You'll find a nice overview here - http://en.wikipedia.org/wiki/ARM_architecture

With a *very* quick look, I wasn't able to find low-cost development boards for these devices. But they sound intriguing.

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There are 10 kinds of people in this world: those who can read binary, and those who can't.

The LPC2368 costs $6.50 in 1k volume. Only issue is that it's a 160pin BGA package, so the circuit board isn't so cheap. The LPC210x has only 48 pins. Keil has a development board for the LPC2368. I've looked pretty closely at this chip, but probably will move toward a multiprocessor LPC210x architecture in future development.

The LPC2368 costs $6.50 in 1k volume. Only issue is that it's a 160pin BGA package, so the circuit board isn't so cheap. The LPC210x has only 48 pins. Keil has a development board for the LPC2368. I've looked pretty closely at this chip, but probably will move toward a multiprocessor LPC210x architecture in future development.

So, are you saying that the board I have suggested is pretty old now? These, after all, were bought half a year ago.

I was also wondering, whether, for the chips you have suggested, is there more cost involved to develop for them?

Are there better boards available for the same rough costing, that are free to develop for?

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"The truth is, you can't hide from the truth, cos the truth is all there is" - Handsome Boy Modeling School

So, are you saying that the board I have suggested is pretty old now? These, after all, were bought half a year ago.

I was also wondering, whether, for the chips you have suggested, is there more cost involved to develop for them?

Are there better boards available for the same rough costing, that are free to develop for?

Just because a chip is newer doesn't necessarily make it better. The LPC2368 draws about 3x as much current as the LPC2106, so the additional functions come at a cost.

It looks like Olimex makes some nice development boards. We use the Embedded Artists boards because we like the engineers at the company, but we could easily work with other boards.

Other than the cost of the hardware, there don't have to be any addeddevelopment costs. Though commercial software packages are available, we use free software (GNUARM) for all of our development. We're not using any hardware debug interfaces (JTAG), but that would be an expense.

We selected the LPC2106 because it's the only ARM7 with 64kb of onboard RAM, and we need the memory for image processing. There are so many ARM7's to choose between, and the choice depends a lot on your i/o requirements. In any case, it's a very easy processor to use, and as your tutor noted, there's no reason to limit yourself computationally to old 8-bit microcontrollers when you have processors available with this kind of capability.

Are there more powerful boards, say, with 1 MB of RAM and a ~25-50 MHz ARM processor? I'm wondering what could be used to build a small walker robot for example (say, something as big as plen the skateboarding robot, using servos to move all limbs). Something powerful enough to do a little bit of vision processing.

Are there more powerful boards, say, with 1 MB of RAM and a ~25-50 MHz ARM processor? I'm wondering what could be used to build a small walker robot for example (say, something as big as plen the skateboarding robot, using servos to move all limbs). Something powerful enough to do a little bit of vision processing.

If you're going to do vision processing, why not have a dedicated DSP?

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There are 10 kinds of people in this world: those who can read binary, and those who can't.

Are there more powerful boards, say, with 1 MB of RAM and a ~25-50 MHz ARM processor? I'm wondering what could be used to build a small walker robot for example (say, something as big as plen the skateboarding robot, using servos to move all limbs). Something powerful enough to do a little bit of vision processing.

If you're going to do vision processing, why not have a dedicated DSP?

What do you mean by a DSP, do you mean an FPGA? I suppose that's an option, but I would still need some algorithmic control in there, so my question still stands...

We do vision processing at relatively low resolution (160x128) in real-time on a 60MIPS ARM7. There are versions of the ARM7 that have an external bus for program and data memory. Here's a pretty good comparison chart -

Note that the ARM7 has a hardware multiple that uses 1-4 clock cycles, depending on word size, and there's also a single cycle barrel shifter, so the ARM7 arithmetic performance is comparable a DSP of similar clock speed.